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Time's up.
I'm not gonna let you see the answer, I wanna know what you think.
How many think:a?
energy was added to break the bond of this ATP sitting in outer space in two pieces.
Okay, how many say b?
Energy was released as this bond was broken. Okay.
Still haven't got most of you. How about c, energy got added to start the bond
breaking but then energy is released?
How about none of the above? ... So,
How about when I break this?
Energy added because I had to do something,
did energy come back out?
A bit later?
Do you have to add ...
The question I'm basically asking is do you have to add energy to break a
bond
or does energy come out somehow and I tried to say it
but maybe I didn't say clearly enough you have to add
energy to break a bond you do not get energy out.
How do you get energy out of something?
Let's do it in reverse, I had to add energy
I have to add energy if I break a bond apart, if I break two things apart.
How would I get energy back? What's the river of that process?
Form some bonds! What happens to
ATP when it breaks into two pieces if it is in outer space
you had to add energy to do it. If it is in liquid
with all the other elements around, it forms a bunch of bonds
and the bonds that form release
more energy than it took to break the initial one.
The whole process
in water, in cells,
releases energy not because the energy comes from the ATP bond
but because the energy comes when you form whatever bonds, whatever other
bonds get formed
in that reaction. Energy does not come out
when you break s bond, it comes out when you form bonds.
You kind of know this
if I had,
if I want to turn this (ball) to a gas to break all the bonds in here
and turn it into a gas, poison gas probably,
full a plastic, but anyway if I want to turn this into a gas
do I add energy? Break a bunch of bonds, do I add energy or take it out?
Add! You really have to heat this up a lot, I'd need a torch
to turn this thing into gas,or a big oven or something.
If I have a gas of this stuff in a container,
really hot, obviously, if its gas, what do I do to make
the bonds form? Take energy out or put it in?
Take it out! You need to take
energy out so that bonds can form.
Either you take it out so that bonds can form
or bonds form and give off that energy.
Some way, somehow. If they can't give off that energy.
they will not form bonds. This gas
of bowling ball right here, the bowling ball gas that I have in some container,
is not going to form into a solid bowling ball
unless it can give off energy. Bonds only get
formed when they can give off some energy somewhere.
So when you learn
in biology that you get energy from ATP breaking up into these two
it's not the breaking up to gets you the energy that actually cost you energy
it's the other things that form that get you the energy. ... So,
I have an ice cube sitting here
I'll let it warm up a bit.
I've liquid nitrogen sitting here and it says it's minus a hundred and
-142 degrees
C. So,
I'm trying to figure out liquid nitrogen,
liquid nitrogen boils at
77 Kelvin, so this is not quite
cold enough.
The thermometer's not so good. It's cold in there though.
Liquid nitrogen sita in there boiling at one atmosphere, which is the world we
live in.
At 77 Kelvin, so down in there this thermometer is supposed to be reading
77 Kelvin,
which is -190 C.
So that thermometer is not very good at these temperatures,
nevertheless my question for you
has to do with this
ice cube that is sitting around. Suppose I take an ice cube from the
freezer
I dip the ice cube into a cup of liquid nitrogen
liquid nitrogen boils, (oh I already said where it boils) I leave it there until the
temperature of the ice cube stops
changing. So the temperature of the ice cube as I put it in there is gonna change.
There's an interaction between the ice cube and the liquid nitrogen,
and that interaction causes the liquid nitrogen to boil even more.
Why is the liquid nitrogen boiling a lot more?
What can I say? It's taking energy from the ice.
What can I say about the chunk of ice?
As far the liquid nitrogen is concerned is the chunk of ice hot
or cold? It's hot.
A chunk of ice sitting here at 0 degrees or something
is a lot hotter than the liquid nitrogen, so heat gets transferred.
What's the final temperature of the ice cube
after the interaction just described?
I'll give you a minute or so to talk about it.